"As London wakes up to the aftermath of a giant party on the Mall and the announcement that the Duke and Duchess of Cambridge have a son, there are hopes that the birth of the new royal baby will spark a tourism boom as well-wishers flock to the UK to share in the joy," Britain's second best-selling paper went on in its picture-rich splash.

"The spell cast by the monarchy's 1,000-year history, combined with the international media frenzy around the royal baby, is extremely powerful at drawing people to England," Lady Cobham, chair of the tourist body VisitBritain, is quoted as saying

"Royal attractions in Edinburgh are expecting a surge in visitor numbers as tourists flock to share in the baby joy," the article said.

Yet further afield (although still in a Commonwealth country) the travel editor of the Star, in Toronto, was not "necessarily gung ho" about the royal family but he still devoted a blog post to the "bounce" it was sure to give British tourism.

On social media, "A British Royal baby could spark a major boost to the UK tourism industry," was a typical comment from Airwise News.

Where's the evidence?

Looking for evidence for the widely touted princeling-tourism connection, the evidence becomes less clear.

Certainly tourists flocked to Buckingham Palace in advance of the birth, awaiting confirmation of the baby's arrival.

"Our holiday was booked months ago, so we did not expect to be over here while the baby was happening [but we've] been told to bring back as many newspapers and souvenirs with the baby on as possible," Matthew and Donna Harold, from Michigan, told the Telegraph.

A scan of social media reveals the odd international prince-fixated quote, such as this from a tweeter in Fort Lauderdale, Florida: "Dear Kate Middleton, Please wait to have the Royal Baby until Thursday. Thank you, Annie Harley, an American Tourist."

But are there any hard numbers to support the idea of a baby-born tourist surge?

The Mail did cite a statistical precedent. In 2012, it said, the Queen's Diamond Jubilee year, tourist visits (at 31 million) were at their highest level since the beginning of the economic downturn in 2008.

However, even if hotels near Kensington Palace are throwing caution to the wind with "Tot-ter Around Kensington" shop-and-stay packages and converting luxury suites into five-star nurseries for the occasion, that still doesn't turn correlation into cause.

Negative effect?

If anything, the numbers point the other way.

A recent story in the Guardian refers to a document obtained under Freedom of Information legislation from Visit Britain on the marriage between Prince Andrew and Sarah Ferguson in 1986.

"We find that across the year as a whole there were 4% fewer visitors to Britain than in 1985, but that in July [1986] there were 8% fewer than in July of 1985," the document says.

"[S]uch as it is, the evidence points to royal weddings having a negative impact on inbound tourism."